Traveling scaffold



1962 G. w. ROBINSON ETAL 3, ,7

TRAVELING SCAFFOLD 2 Sheets-Sheet 1 Filed May 9, 1961 INVENTQRJ GERFILDW- Rosmsomm ROBERT E. Spsncsw.

Tau, 7 7 M 75mm 5 TTORNEYS Dec. 4, 1962 Filed May 9, 1961 2 Sheets-Sheet2 m H 3 3 V INV NTORS Gamma W., oamsoum Roam- B. SPENCER United StatesPatent Ofifice 3,%fi,757 Patented Dec. 4, 1962 'i ii This inventionrelates in general to traveling or movable scaffolds, and moreparticularly relates to a traveling scaffold for use with bridges andlike elevated structures.

In the construction of reinforced concrete bridges and the like, thebridge is often formed of elongated parallel girders or stringers, suchas I-beams, supported on more or less vertical pier constructions. Thebridge deck is supported on the tops of the I-beam stringers, and oftenis provided with lateral overhangs of reinforced concrete, for use suchas sidewalk areas on the bridge. The installation and removal of thenecessary forms for producing such overhanging portions presents manyproblems, and after the forms are removed, it is conventionallynecessary to place cement finishers in the proximity of such overhangingportions for finishing the surfaces of the exposed concrete sections.The above work problems usually necessitate the erection of a more orless stationary scaffolding from ground level which erection is costlyand time consuming.

The present invention comprises a light weight, rolling scaffold of thecantilever type, which can be readily mounted for lengthwise movement onthe outermost stringer on a side of the bridge construction and whichprovides for the convenient erection and removal of the necessarypouring forms for the aforementioned overhanging portions of the bridgedeck, and which provides for effectively placing workmen, such as cementfinishers, in convenient access to the exposed concrete surfacesconstituting such overhanging portions.

Accordingly, an object of the invention is to provide an improvedconstruction of rolling scaffold for bridges and the like.

Another object of the invention is to provide a scaffold of the lattertype which can be readily disassembled and assembled and which can beeasily moved lengthwise of the bridge in cantilever mounted fashion onan outermost flanged stringer element on a side of the bridgeconstruction, for providing a platform utilizable in erecting andremoving concrete forms for overhanging portions of the bridge deck, andfor finishing the concrete surfaces of such portions.

A more specific object of the invention of to provide a rolling bridgescaffold of the above discussed type wherein the platform surface of thescaffold is adjustable in a generally vertical direction, therebyproviding for expediting various work operations on the bridge by theworkmen, and wherein the scaffold comprises a plurality of sectionsdetachably connected in longitudinally aligned relation to one another,so that when the movable scaffold approaches a vertical obstruction onthe bridge, as for instance one of the aforementioned pierconstructions, one section of the scaffold can be dismantled and movedahead of the obstruction, working from the nondismantled sections, andthen the following sections can be progressively dismantled working fromthe reassembled transferred section and moving such sections in front ofthe first transferred section, thereby providing for travel of thescaffold the entire length of the bridge stringer, and from onesupporting pier abutment to the other irrespective of such obstructions.

Other objects and advantages of the invention will be apparent from thefollowing description taken in conjunction with the accompanyingdrawings wherein:

FIG. 1 is a more or less diagrammatic, perspective view A. of a bridgeconstruction having a scaffold of the invention mounted thereon;

FIG. 2 is an enlarged end sectional view of the scafiold construction asmounted on an I-bearn stringer of a bridge;

FIG. 3 is an enlarged end view of one of the rolling brackets fordetachably mounting the scaffold in movable relation on the I-beamstringer and is a view taken generally along the plane of line 33 ofFIG. 2, looking in the direction of the arrows;

FIG. 4 is a view generally similar to that of FIG. 3, but illustrating aview of another of the rolling brackets of the scaffold, as takengenerally along the plane of line 4-4 of FIG. 2, looking in thedirection of the arrows;

FIG. 5 is a fragmentary, end elevational view taken generally along theplane of line 5-5 of FIG. 2, looking in the direction of the arrows, andillustrating the structure of the platform which aids in facilitatingmovement of the scaffold about obstructions in the lengthwise extent ofthe supporting bridge girder.

Referring now especially to FIG. 1, there is illus trated a bridgeconstruction comprising a plurality of generally parallel extendingstringers A supported on pier contruction B. The bridge construction mayinclude overhanging portions C which are adapted to provide sidewalkareas or the like on the bridge. The formation of such overhangingportions necessitates installation of forms D extending outwardly fromthe outer face of the outermost stringer 8 on a respective side of thebridge construction.

Now in accordance with the instant invention, there is provided a novelrolling scaffold ill) for mounting on the outermost stringer 8 on a sideof the bridge construction, and which scaffold is movable lengthwisetherealong for providing for the ready and effective installation andremoval of the concrete forms D, and for finishing of the exposed facesof the concrete, after the forms have been removed, by placing workmenin close proximity to such exposed faces. Such a scaffold preferablycomprises two or more sections (e.g. 11 and 12) detachably connectedtogether so that when the scaffold approaches an obstruction in thelengthwise extent of the associated stringer, such as for instance apier construction, the rearwardmost section can be readily dismantledfrom the other section or sections, and working from the non-dismantledsection, the dismantled section can be reassembled ahead of theobstruction, and then progressively the other sections can be dissembledand placed in reassembled condition in front of the first transferredsection, whereby providing for travel of the scaffold the entire lengthof a bridge girder, and from one pier abutment to the other. The latterprocedure will hereinafter be described in greater detail.

The scaffold construction comprises a plurality of longitudinally spacedbase or hanger portions 16 on which is mounted in cantilever fashion arespective platform supporting portion 18 of the scaffold. Each hangerportion 16 comprises transversely spaced hanger bracket members 2% and22. Referring in particular to FIG. 3 bracket member 20, in theembodiment illustrated, is of L-shape in end elevation comprising a basesection 22a and a generally elongated upstanding section 22b. Upstandingsection 2219 has a plurality of longitudinally spaced roller members 24rotatably mounted thereon and adapted for rolling engagement with theunderside of the flange 25 of the l-beam stringer 8. Disposed above andin oifset relation with respect to rollers 24 are friction bearing meansor hardened balls 26, rotatably mounted in upstanding section 2211 andadapted for engagement with the confronting side surface 25' of flange25. Roller members 24- are preferably mounted in anti-friction bearings,such as needle bearings, for ease of rotation. Bracket member 26 may beattached to the top surface of horizontal arm 27 of the hanger portion16, as by means of nut and bolt assembly 28 and with such bracket beingpreferably adjustably attached to such top surface as by means of anelongated slot in the surface, receiving therethrough the bolt and nutassembly 28, for adjusting the position of hanger bracket with respectto hanger bracket 22, and thereby providing for various widths offlanges on an l-beam stringer. portion 16 is also provided with adepending leg section 36, which has vertically spaced openings (eg. 32)provided through a flange thereof, for adjusting the vertical positionof the platform section 18 with respect to the hanger section 16, aswill be hereinafter further discussed. Hanger section 16 also preferablyincludes diagonal tube brace members 34-, which strengthen and rigidifythe scaffold hanger portion 16.

The other hanger bracket 22 comprises a base section 35 attached to theupper surface of arm 27, as by means of bolt and nut assemblies 36, agenerally elongated upstanding seciton 3%, and a head section 4%overhanging the base section of the respective bracket.

Mounted on head section 46 are a plurality of longitudinally spacedroller members 42, which are adapted for rolling engagement with theupper surface of flange 25 of the I-beam 8. Disposed below and in offsetrelation with respect to rollers 42 are a plurality of longitudinallyspaced friction bearing means or balls 44, which are adapted forengagement with the confronting side surface 25 of flange 25. A scrapertongue 46 is disposed outwardly of each of roller members 42, whichscraper tongues are adapted to shove any concrete particles or the like,which have fallen onto the top surface 25 of flange 25, out of the wayof the roller members 42, thus assuring smooth and uninterruptedmovement of the roller members along the top surface of flange 25.

The hanger portions 16 may be secured together by diagonal brace members48 (FIGS. 1 and 2), thus attaching a pair of such hanger portionstogether for movement as a unit on the I-beam 8. Three of such hangerportions 16 may be utilized to form the aforementioned detachablesections 11 and 12 of the rolling scaffold, with such connecting bracemembers 48 detachably connecting such hanger sections 16 together as bymeans of fastener assemblies 50, for ready detachment of such connectedhanger sections 16 with respect to one another.

As aforementioned, a platform supporting section 18 is detachablysecured to the leg of the respective hanger section 16, as by means ofnut and bolt assemblies 52. Section 18 comprises an upstanding armelement 54 having vertically aligned apertures, and a horizontal arm,element 56 secured to arm 54 in cantilever fashion and as by means offastener assemblies 58. A diagonal brace member 66 may be providedextending from upright arm 54 as at 61, to a point adjacent the outerend of horizontal arm 56, as at 62, to provide additional support forsuch horizontal arm. Horizontal arm 56 preferably has supporting flanges64 (FIG. 5) extending from both sides thereof, and elongated stringers66 extending parallel to girder 8 are supported on and detachablyconnected to such flanges 64, as by means of threaded bolts 68. Bolts 68are adapted to be secured in complementary threaded openings in therespective flange 64, and hold stringers 66 in assembled position. Itwill be seen that flanges 64 on both sides of arm 56 of platformsupporting portion 18 provide for the expeditious use of only threesupporting portions 18, to form a pair of connected scaffold sections 11and 12, and provide for the interchangeability of portions 18, whetherthey are used at the leading or following end of the respective scaffoldsection.

A railing structure 611 may be provided extending Hanger around at leastone of scaffold sections 11 and 12 for increasing the safety andsecurity to workmen working on the movable scaffold. A workmansupporting sheet 70 of plywood or some other suitable material may bemounted on the tops of stringers 66 and extending between the adjacentplatform supporting portions 18.

As best illustrated in FIG. 2, section 18 can be oriented in a pluralityof vertically disposed positions with respect to the respective hangersection 16 by removing the attaching bolt and nut assemblies 52 andreassembling the platform supporting portion 1% at a different verticalposition. In the embodiment illustrated, there are eleven possiblepositions of the platform supporting portion 18 with respect to therespective hanger portion 16. When the platform supporting portion 18 ismoved to the upper ones of its possible vertical positions with respectto hanger portion 16, the diagonal bracing member 66 may be shifteddownwardly and attached underneath the horizontal arm 56, rather thanbeing disposed upwardly above the horizontal arm 56 and as shown indashed lines in FIG. 2.

If an obstruction is met in the travel of the scaffolding along theI-beam stringer 8, as for instance when the scafiold comes up to one ofthe pier constructions supporting the stringer, the, trailing portions16 and 18 of scaffold section 11 can be disassembled and moved ahead ofthe obstruction, and then the other section or sections (eg. 12) can bedisassembled and moved ahead of the transferred section, to provide fortravel of the scaffold the entire length of the bridge stringer, andfrom one supporting pier abutment to the other. For instance, theplatform 76 on the section 11 may be placed on section 12 to permitremoval of fasteners from the central one of portions 18', and thediagonal brace members 43 of section 11 may be detached, therebypermitting drawing of the following end portions 16 and 18 of section 11toward section 12. Disassembly of the stringers 66 from the followingportion 18 of section 11 can then be readily accomplished working fromsection 12. Following end portions 16 and 16 of section 11 may then bereadily detached from girder 8 by rotating such portions in acounterclockwise direction, with respect to FIG. 2, whereupon, thefriction balls 26 are snapped out of engaging relation with surface 25of flange 25. The portions 16 and 18 are preferably formed of highstrength, but light weight aluminum or other suitable light weightmaterial, Which facilitates their handling by the workmen. Thedisassembled scaffold portions. 16 and 18 may then be reassembled on thegirder 8 ahead of the obstruction, by merely placing the rollers 42 ofhanger bracket 22, on the flange 25, and rotating the portions 16 and 18in a clockwise direction (with respect to FIG. 2) whereupon the frictionballs 26 snap into engagement with surface 25 of the girder and therollers 24 engage the underside of flange 25, and thus once moresecurely mount portion 16 and associated portion 18 in dependingrelation from girder 8. Stringers 66 may then be secured to flange 64 onhorizontal arm 56 and the platform board placed thereon to form ascaffold section bridging the obstruction. The aforemen tioned centralone. of portions 18 (which now represents the following end of thescaffold construction) may then be disassembled in a like manner andmoved ahead of the first transferred section and then reassemled, and soon until all sections of the scaffold have been transferred ahead of theobstruction. The lightness of weight, ready detachability of the bracingmembers 48 and platform supporting stringers 66, and the readydetachability and attachability of the hanger bracket members 20 and 22from and to the girder 8, provides for the expeditious movement of thescaffold sections around an obstruction. Also, as may be best seen fromFIG. 5, the railing posts '75 merely set in brackets 76 attached toplatform portion 18, and are detachably connected as at 78 to theupright arms 54, for ease of assembly and disassembly of such railingstructure.

From the foregoing discussion and accompanying drawings, it will be seenthat the invention provides a lightweight rolling scaffold which can bereadily disassembled and assembled and which can be easily movedlengthwise of the bridge in cantilever mounted fashion on an outermostflange stringer element on a side of the bridge construction, forproviding a platform utilizable in erecting and removing concrete formsfor overhanging portions of the bridge deck and for finishing theconcrete surfaces of such portions.

The terms and expressions which have been utilized are used as terms ofdescription and not of limitation and there is no intention in the useof such terms and expressions of excluding any equivalents of any of thefeatures shown or described, or portions thereof, but it is recognizedthat various modifications are possible within the scope of theinvention claimed.

We claim:

1. A traveling scaffold of light material, such as aluminum, for bridgesand like elevated structure, where in said structure includes alengthwise extending girder, such as an I-beam, having an exposed bottomflange thereon, said scaffold comprising a hanger section includingvertically and transversely spaced roller means for mounting said hangersection in suspended movable relation on the girder flange, and aplatform supporting section detachably secured to said hanger section inoutward laterally disposed cantilever relationship therewith, saidhanger section comprising a plurality of lengthwise spaced hanger framesof inverted and reversed L-shaped configuration and bracing meansextending between and detachably connected to said frames to couple thelatter as a unit, each of said hanger frames including a pair oftransversely spaced hanger brackets projecting upwardly therefrom, saidbrackets mounting said roller means in anti-friction bearings thereon,the roller means on one of said brackets being adapted for rollingengagement with the upper surface of the girder flange, the roller meanson the other of the brackets being adapted for rolling engagement withthe undersurface of the girder flange, and friction ball means mountedin said brackets in vertically oriented relationship to the respectiveroller means, said ball means in said one bracket being disposed belowthe associated roller means, and said ball means in said other bracketbeing disposed above the associated roller means, said ball means beingadapted for engagement with the respective confronting side surface ofthe girder flange for detachably coupling in snap fastening relation thescaffold to the girder flange, said platform section comprising aplurality of frames, each of one of which is detachably connected to arespective one of said hange frames, each of said platform framescomprising a generally horizontally disposed laterally extending armincluding flange means on opposite sides of said arm, and lengthwise extending between and being detachably secured at opposite ends to therespective of said flange means, said stringer means being adapted tomount a workman supporting platform on the top surface thereof.

2. A traveling scaffold in accordance with claim 1, wherein saidplatform section and said hanger section includes means for adjustingthe vertical position of said platform section with respect to saidhanger section.

References Cited in the file of this patent UNITED STATES PATENTS2,253,256 Wehr Aug. 19, 1941 2,414,538 Lamb Jan. 21, 1947 2,543,348Briese Feb. 27, 1951 2,730,411 Krane Jan. 10, 1956 2,925,240 LavioletteFeb. 16, 1960 FOREIGN PATENTS 253,875 Germany Nov. 18, 1912

